Chemical manufacturers are under fire (again) for their use of poly- and perfluoroalkyl substances (PFASs), which are chemicals commonly used to make thousands of products.

The concern comes from a group of international scientists featured in the May issue of the journal Environmental Health Perspectives. Years ago, The New York Times reported, manufacturers like DuPont banned the use of PFASs after studies showed they linger in the body and increase risk for cancer and other health problems. Now, scientists find the replacement chemicals are merely “short-chain PFASs with similar structures.”

“PFASs are found in the indoor and outdoor environments, wildlife, and human tissue and bodily fluids all over the globe,” scientists explained. “They are emitted via industrial processes and military and firefighting operations, and they migrate out of consumer products into air, household dust, food, soil, ground and surface water, and make their way into drinking water.”

In animals, PFASs have been shown to cause liver toxicity and disrupt metabolism and immune system. And some PFASs have even been listed under the Stockholm Convention as persistent organic pollutants (POPs). In which case, scientists called for global action.

The action plan would be a five-pronged approach: scientists, governments, chemical manufacturers, product manufacturers, and consumers would all play a roll in eliminating the use and spread of PFASs. For example, scientists would need to assemble and collaborate with industry and governments to develop analytical methods to identify and quantify the families of PFASs, as well as their replacements or alternatives.

“Research is needed to find safe alternatives for all current uses of PFASs,” Linda S. Birnbaum, the head of the national toxicology program for the Department of Health and Human Services, said in a statement. “The question is, should these chemicals continue to be used in consumer products in the meantime, given their persistence in the environment?”

The American Chemistry Council, the Times cited, counterpointed the EHP’s warning by saying scientists “ignored the fact that such chemicals use ‘essential technology for many aspects of modern life,’ and that tests, reviewed by the Environmental Protection Agency, concluded that these alternatives were safer than the chemicals they were replacing.” Not to mention the use of these chemicals contribute to the billions of sales manufacturers, like DuPont, make.

“We don’t dismiss the right of folks to debate this,” Thomas H. Samples, DuPont’s head of risk management for the division that manufactures these chemicals, said. “But we just believe based on the 10-year history of extensive studies done on the alternatives, that the regulatory agencies have done their job of determining that these things are safe for their intended uses.”